| blob | ae031df477f939a401182e0585626af340f4ca30 |
1 /* PowerPC-specific support for 32-bit ELF
2 Copyright 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
3 2004, 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
4 Written by Ian Lance Taylor, Cygnus Support.
6 This file is part of BFD, the Binary File Descriptor library.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the
20 Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
21 Boston, MA 02110-1301, USA. */
24 /* This file is based on a preliminary PowerPC ELF ABI. The
25 information may not match the final PowerPC ELF ABI. It includes
26 suggestions from the in-progress Embedded PowerPC ABI, and that
27 information may also not match. */
30 #include <stdarg.h>
39 /* RELA relocations are used here. */
41 static bfd_reloc_status_type ppc_elf_addr16_ha_reloc
43 static bfd_reloc_status_type ppc_elf_unhandled_reloc
46 /* Branch prediction bit for branch taken relocs. */
47 #define BRANCH_PREDICT_BIT 0x200000
48 /* Mask to set RA in memory instructions. */
49 #define RA_REGISTER_MASK 0x001f0000
50 /* Value to shift register by to insert RA. */
51 #define RA_REGISTER_SHIFT 16
53 /* The name of the dynamic interpreter. This is put in the .interp
54 section. */
57 /* For old-style PLT. */
58 /* The number of single-slot PLT entries (the rest use two slots). */
59 #define PLT_NUM_SINGLE_ENTRIES 8192
61 /* For new-style .glink and .plt. */
62 #define GLINK_PLTRESOLVE 16*4
63 #define GLINK_ENTRY_SIZE 4*4
65 /* VxWorks uses its own plt layout, filled in by the static linker. */
67 /* The standard VxWorks PLT entry. */
68 #define VXWORKS_PLT_ENTRY_SIZE 32
69 static const bfd_vma ppc_elf_vxworks_plt_entry
71 {
80 };
81 static const bfd_vma ppc_elf_vxworks_pic_plt_entry
83 {
92 };
94 /* The initial VxWorks PLT entry. */
95 #define VXWORKS_PLT_INITIAL_ENTRY_SIZE 32
96 static const bfd_vma ppc_elf_vxworks_plt0_entry
98 {
107 };
108 static const bfd_vma ppc_elf_vxworks_pic_plt0_entry
110 {
119 };
121 /* For executables, we have some additional relocations in
122 .rela.plt.unloaded, for the kernel loader. */
124 /* The number of non-JMP_SLOT relocations per PLT0 slot. */
125 #define VXWORKS_PLT_NON_JMP_SLOT_RELOCS 3
126 /* The number of relocations in the PLTResolve slot. */
127 #define VXWORKS_PLTRESOLVE_RELOCS 2
128 /* The number of relocations in the PLTResolve slot when when creating
129 a shared library. */
130 #define VXWORKS_PLTRESOLVE_RELOCS_SHLIB 0
132 /* Some instructions. */
133 #define ADDIS_11_11 0x3d6b0000
134 #define ADDIS_11_30 0x3d7e0000
135 #define ADDIS_12_12 0x3d8c0000
136 #define ADDI_11_11 0x396b0000
137 #define ADD_0_11_11 0x7c0b5a14
138 #define ADD_11_0_11 0x7d605a14
139 #define B 0x48000000
140 #define BCL_20_31 0x429f0005
141 #define BCTR 0x4e800420
142 #define LIS_11 0x3d600000
143 #define LIS_12 0x3d800000
144 #define LWZU_0_12 0x840c0000
145 #define LWZ_0_12 0x800c0000
146 #define LWZ_11_11 0x816b0000
147 #define LWZ_11_30 0x817e0000
148 #define LWZ_12_12 0x818c0000
149 #define MFLR_0 0x7c0802a6
150 #define MFLR_12 0x7d8802a6
151 #define MTCTR_0 0x7c0903a6
152 #define MTCTR_11 0x7d6903a6
153 #define MTLR_0 0x7c0803a6
154 #define NOP 0x60000000
155 #define SUB_11_11_12 0x7d6c5850
157 /* Offset of tp and dtp pointers from start of TLS block. */
158 #define TP_OFFSET 0x7000
159 #define DTP_OFFSET 0x8000
161 /* The value of a defined global symbol. */
162 #define SYM_VAL(SYM) \
163 ((SYM)->root.u.def.section->output_section->vma \
164 + (SYM)->root.u.def.section->output_offset \
165 + (SYM)->root.u.def.value)
166 \f
170 /* This reloc does nothing. */
185 /* A standard 32 bit relocation. */
200 /* An absolute 26 bit branch; the lower two bits must be zero.
201 FIXME: we don't check that, we just clear them. */
216 /* A standard 16 bit relocation. */
231 /* A 16 bit relocation without overflow. */
246 /* The high order 16 bits of an address. */
261 /* The high order 16 bits of an address, plus 1 if the contents of
262 the low 16 bits, treated as a signed number, is negative. */
277 /* An absolute 16 bit branch; the lower two bits must be zero.
278 FIXME: we don't check that, we just clear them. */
293 /* An absolute 16 bit branch, for which bit 10 should be set to
294 indicate that the branch is expected to be taken. The lower two
295 bits must be zero. */
310 /* An absolute 16 bit branch, for which bit 10 should be set to
311 indicate that the branch is not expected to be taken. The lower
312 two bits must be zero. */
327 /* A relative 26 bit branch; the lower two bits must be zero. */
342 /* A relative 16 bit branch; the lower two bits must be zero. */
357 /* A relative 16 bit branch. Bit 10 should be set to indicate that
358 the branch is expected to be taken. The lower two bits must be
359 zero. */
374 /* A relative 16 bit branch. Bit 10 should be set to indicate that
375 the branch is not expected to be taken. The lower two bits must
376 be zero. */
391 /* Like R_PPC_ADDR16, but referring to the GOT table entry for the
392 symbol. */
407 /* Like R_PPC_ADDR16_LO, but referring to the GOT table entry for
408 the symbol. */
423 /* Like R_PPC_ADDR16_HI, but referring to the GOT table entry for
424 the symbol. */
439 /* Like R_PPC_ADDR16_HA, but referring to the GOT table entry for
440 the symbol. */
455 /* Like R_PPC_REL24, but referring to the procedure linkage table
456 entry for the symbol. */
471 /* This is used only by the dynamic linker. The symbol should exist
472 both in the object being run and in some shared library. The
473 dynamic linker copies the data addressed by the symbol from the
474 shared library into the object, because the object being
475 run has to have the data at some particular address. */
490 /* Like R_PPC_ADDR32, but used when setting global offset table
491 entries. */
506 /* Marks a procedure linkage table entry for a symbol. */
521 /* Used only by the dynamic linker. When the object is run, this
522 longword is set to the load address of the object, plus the
523 addend. */
538 /* Like R_PPC_REL24, but uses the value of the symbol within the
539 object rather than the final value. Normally used for
540 _GLOBAL_OFFSET_TABLE_. */
555 /* Like R_PPC_ADDR32, but may be unaligned. */
570 /* Like R_PPC_ADDR16, but may be unaligned. */
585 /* 32-bit PC relative */
600 /* 32-bit relocation to the symbol's procedure linkage table.
601 FIXME: not supported. */
616 /* 32-bit PC relative relocation to the symbol's procedure linkage table.
617 FIXME: not supported. */
632 /* Like R_PPC_ADDR16_LO, but referring to the PLT table entry for
633 the symbol. */
648 /* Like R_PPC_ADDR16_HI, but referring to the PLT table entry for
649 the symbol. */
664 /* Like R_PPC_ADDR16_HA, but referring to the PLT table entry for
665 the symbol. */
680 /* A sign-extended 16 bit value relative to _SDA_BASE_, for use with
681 small data items. */
696 /* 16-bit section relative relocation. */
711 /* 16-bit lower half section relative relocation. */
726 /* 16-bit upper half section relative relocation. */
741 /* 16-bit upper half adjusted section relative relocation. */
756 /* Marker relocs for TLS. */
799 /* Computes the load module index of the load module that contains the
800 definition of its TLS sym. */
815 /* Computes a dtv-relative displacement, the difference between the value
816 of sym+add and the base address of the thread-local storage block that
817 contains the definition of sym, minus 0x8000. */
832 /* A 16 bit dtprel reloc. */
847 /* Like DTPREL16, but no overflow. */
862 /* Like DTPREL16_LO, but next higher group of 16 bits. */
877 /* Like DTPREL16_HI, but adjust for low 16 bits. */
892 /* Computes a tp-relative displacement, the difference between the value of
893 sym+add and the value of the thread pointer (r13). */
908 /* A 16 bit tprel reloc. */
923 /* Like TPREL16, but no overflow. */
938 /* Like TPREL16_LO, but next higher group of 16 bits. */
953 /* Like TPREL16_HI, but adjust for low 16 bits. */
968 /* Allocates two contiguous entries in the GOT to hold a tls_index structure,
969 with values (sym+add)@dtpmod and (sym+add)@dtprel, and computes the offset
970 to the first entry. */
985 /* Like GOT_TLSGD16, but no overflow. */
1000 /* Like GOT_TLSGD16_LO, but next higher group of 16 bits. */
1015 /* Like GOT_TLSGD16_HI, but adjust for low 16 bits. */
1030 /* Allocates two contiguous entries in the GOT to hold a tls_index structure,
1031 with values (sym+add)@dtpmod and zero, and computes the offset to the
1032 first entry. */
1047 /* Like GOT_TLSLD16, but no overflow. */
1062 /* Like GOT_TLSLD16_LO, but next higher group of 16 bits. */
1077 /* Like GOT_TLSLD16_HI, but adjust for low 16 bits. */
1092 /* Allocates an entry in the GOT with value (sym+add)@dtprel, and computes
1093 the offset to the entry. */
1108 /* Like GOT_DTPREL16, but no overflow. */
1123 /* Like GOT_DTPREL16_LO, but next higher group of 16 bits. */
1138 /* Like GOT_DTPREL16_HI, but adjust for low 16 bits. */
1153 /* Allocates an entry in the GOT with value (sym+add)@tprel, and computes the
1154 offset to the entry. */
1169 /* Like GOT_TPREL16, but no overflow. */
1184 /* Like GOT_TPREL16_LO, but next higher group of 16 bits. */
1199 /* Like GOT_TPREL16_HI, but adjust for low 16 bits. */
1214 /* The remaining relocs are from the Embedded ELF ABI, and are not
1215 in the SVR4 ELF ABI. */
1217 /* 32 bit value resulting from the addend minus the symbol. */
1232 /* 16 bit value resulting from the addend minus the symbol. */
1247 /* 16 bit value resulting from the addend minus the symbol. */
1262 /* The high order 16 bits of the addend minus the symbol. */
1277 /* The high order 16 bits of the result of the addend minus the address,
1278 plus 1 if the contents of the low 16 bits, treated as a signed number,
1279 is negative. */
1294 /* 16 bit value resulting from allocating a 4 byte word to hold an
1295 address in the .sdata section, and returning the offset from
1296 _SDA_BASE_ for that relocation. */
1311 /* 16 bit value resulting from allocating a 4 byte word to hold an
1312 address in the .sdata2 section, and returning the offset from
1313 _SDA2_BASE_ for that relocation. */
1328 /* A sign-extended 16 bit value relative to _SDA2_BASE_, for use with
1329 small data items. */
1344 /* Relocate against either _SDA_BASE_ or _SDA2_BASE_, filling in the 16 bit
1345 signed offset from the appropriate base, and filling in the register
1346 field with the appropriate register (0, 2, or 13). */
1361 /* Relocation not handled: R_PPC_EMB_MRKREF */
1362 /* Relocation not handled: R_PPC_EMB_RELSEC16 */
1363 /* Relocation not handled: R_PPC_EMB_RELST_LO */
1364 /* Relocation not handled: R_PPC_EMB_RELST_HI */
1365 /* Relocation not handled: R_PPC_EMB_RELST_HA */
1366 /* Relocation not handled: R_PPC_EMB_BIT_FLD */
1368 /* PC relative relocation against either _SDA_BASE_ or _SDA2_BASE_, filling
1369 in the 16 bit signed offset from the appropriate base, and filling in the
1370 register field with the appropriate register (0, 2, or 13). */
1399 /* A 16 bit relative relocation. */
1414 /* A 16 bit relative relocation without overflow. */
1429 /* The high order 16 bits of a relative address. */
1444 /* The high order 16 bits of a relative address, plus 1 if the contents of
1445 the low 16 bits, treated as a signed number, is negative. */
1460 /* GNU extension to record C++ vtable hierarchy. */
1475 /* GNU extension to record C++ vtable member usage. */
1490 /* Phony reloc to handle AIX style TOC entries. */
1504 };
1505 \f
1506 /* Initialize the ppc_elf_howto_table, so that linear accesses can be done. */
1508 static void
1510 {
1515 i++)
1516 {
1522 }
1523 }
1527 bfd_reloc_code_real_type code)
1528 {
1531 /* Initialize howto table if not already done. */
1536 {
1627 }
1630 };
1635 {
1640 i++)
1646 }
1648 /* Set the howto pointer for a PowerPC ELF reloc. */
1650 static void
1654 {
1655 /* Initialize howto table if not already done. */
1662 /* Just because the above assert didn't trigger doesn't mean that
1663 ELF32_R_TYPE (dst->r_info) is necessarily a valid relocation. */
1665 {
1671 }
1672 }
1674 /* Handle the R_PPC_ADDR16_HA and R_PPC_REL16_HA relocs. */
1676 static bfd_reloc_status_type
1684 {
1685 bfd_vma relocation;
1688 {
1691 }
1698 else
1710 }
1712 static bfd_reloc_status_type
1720 {
1721 /* If this is a relocatable link (output_bfd test tells us), just
1722 call the generic function. Any adjustment will be done at final
1723 link time. */
1729 {
1734 }
1736 }
1737 \f
1738 /* Sections created by the linker. */
1741 {
1742 /* Pointer to the bfd section. */
1744 /* Section name. */
1746 /* Associated bss section name. */
1748 /* Associated symbol name. */
1750 /* Associated symbol. */
1754 /* Linked list of allocated pointer entries. This hangs off of the
1755 symbol lists, and provides allows us to return different pointers,
1756 based on different addend's. */
1759 {
1760 /* next allocated pointer for this symbol */
1762 /* offset of pointer from beginning of section */
1763 bfd_vma offset;
1764 /* addend used */
1765 bfd_vma addend;
1766 /* which linker section this is */
1770 struct ppc_elf_obj_tdata
1771 {
1774 /* A mapping from local symbols to offsets into the various linker
1775 sections added. This is index by the symbol index. */
1778 /* Flags used to auto-detect plt type. */
1781 };
1783 #define ppc_elf_tdata(bfd) \
1784 ((struct ppc_elf_obj_tdata *) (bfd)->tdata.any)
1786 #define elf_local_ptr_offsets(bfd) \
1787 (ppc_elf_tdata (bfd)->linker_section_pointers)
1789 #define is_ppc_elf(bfd) \
1790 (bfd_get_flavour (bfd) == bfd_target_elf_flavour \
1791 && elf_object_id (bfd) == PPC32_ELF_TDATA)
1793 /* Override the generic function because we store some extras. */
1795 static bfd_boolean
1797 {
1799 PPC32_ELF_TDATA);
1800 }
1802 /* Fix bad default arch selected for a 32 bit input bfd when the
1803 default is 64 bit. */
1805 static bfd_boolean
1807 {
1809 {
1813 {
1814 /* Relies on arch after 64 bit default being 32 bit default. */
1817 }
1818 }
1820 }
1822 /* Function to set whether a module needs the -mrelocatable bit set. */
1824 static bfd_boolean
1826 {
1833 }
1835 /* Support for core dump NOTE sections. */
1837 static bfd_boolean
1839 {
1844 {
1849 /* pr_cursig */
1852 /* pr_pid */
1855 /* pr_reg */
1860 }
1862 /* Make a ".reg/999" section. */
1865 }
1867 static bfd_boolean
1869 {
1871 {
1880 }
1882 /* Note that for some reason, a spurious space is tacked
1883 onto the end of the args in some (at least one anyway)
1884 implementations, so strip it off if it exists. */
1886 {
1892 }
1895 }
1899 {
1901 {
1906 {
1917 }
1920 {
1939 }
1940 }
1941 }
1943 /* Return address for Ith PLT stub in section PLT, for relocation REL
1944 or (bfd_vma) -1 if it should not be included. */
1946 static bfd_vma
1950 {
1952 }
1954 /* Handle a PowerPC specific section when reading an object file. This
1955 is called when bfd_section_from_shdr finds a section with an unknown
1956 type. */
1958 static bfd_boolean
1963 {
1965 flagword flags;
1980 }
1982 /* Set up any other section flags and such that may be necessary. */
1984 static bfd_boolean
1988 {
1996 }
1998 /* If we have .sbss2 or .PPC.EMB.sbss0 output sections, we
1999 need to bump up the number of section headers. */
2001 static int
2004 {
2017 }
2019 /* Add extra PPC sections -- Note, for now, make .sbss2 and
2020 .PPC.EMB.sbss0 a normal section, and not a bss section so
2021 that the linker doesn't crater when trying to make more than
2022 2 sections. */
2025 {
2036 };
2038 /* This is what we want for new plt/got. */
2044 {
2047 /* See if this is one of the special sections. */
2054 {
2058 }
2061 }
2062 \f
2063 /* Very simple linked list structure for recording apuinfo values. */
2065 {
2068 }
2069 apuinfo_list;
2074 static void
2076 {
2078 }
2080 static void
2082 {
2086 {
2090 }
2099 }
2101 static unsigned
2103 {
2108 entry;
2113 }
2117 {
2123 ;
2126 }
2128 static void
2130 {
2134 {
2138 }
2141 }
2146 /* Scan the input BFDs and create a linked list of
2147 the APUinfo values that will need to be emitted. */
2149 static void
2151 {
2156 bfd_size_type output_section_size;
2166 /* Scan the input bfds, looking for apuinfo sections. */
2171 {
2174 {
2177 }
2178 }
2180 /* We need at least one input sections
2181 in order to make merging worthwhile. */
2185 /* Just make sure that the output section exists as well. */
2190 /* Allocate a buffer for the contents of the input sections. */
2198 /* Read in the input sections contents. */
2200 {
2210 {
2213 }
2217 {
2220 }
2222 /* Process the contents of the section. */
2226 /* Verify the contents of the header. Note - we have to
2227 extract the values this way in order to allow for a
2228 host whose endian-ness is different from the target. */
2240 /* Get the number of bytes used for apuinfo entries. */
2245 /* Make sure that we do not run off the end of the section. */
2249 /* Scan the apuinfo section, building a list of apuinfo numbers. */
2253 /* Update the offset. */
2255 }
2259 /* Compute the size of the output section. */
2269 fail:
2274 }
2276 /* Prevent the output section from accumulating the input sections'
2277 contents. We have already stored this in our linked list structure. */
2279 static bfd_boolean
2284 {
2287 }
2289 /* Finally we can generate the output section. */
2291 static void
2293 {
2298 bfd_size_type length;
2313 {
2317 }
2319 /* Create the apuinfo header. */
2328 {
2331 }
2342 }
2343 \f
2344 static bfd_boolean
2346 {
2356 }
2358 static bfd_boolean
2360 {
2365 }
2367 static long
2371 {
2376 bfd_vma stub_vma;
2400 /* Call common code to handle old-style executable PLTs. */
2405 /* If this object was prelinked, the prelinker stored the address
2406 of .glink at got[1]. If it wasn't prelinked, got[1] will be zero. */
2409 {
2423 {
2424 Elf_Internal_Dyn dyn;
2431 {
2439 }
2440 }
2442 }
2444 /* Otherwise we read the first plt entry. */
2446 {
2449 }
2454 /* The .glink section usually does not survive the final
2455 link; search for the section (usually .text) where the
2456 glink stubs now reside. */
2461 /* Determine glink PLT resolver by reading the relative branch
2462 from the first glink stub. */
2465 {
2468 /* The first glink stub may either branch to the resolver ... */
2473 /* ... or fall through a bunch of NOPs. */
2480 {
2483 }
2484 }
2488 /* If the stubs are those for -shared/-pie then we might have
2489 multiple stubs for each plt entry. If that is the case then
2490 there is no way to associate stubs with their plt entries short
2491 of figuring out the GOT pointer value used in the stub. */
2503 {
2507 }
2521 {
2525 /* Undefined syms won't have BSF_LOCAL or BSF_GLOBAL set. Since
2526 we are defining a symbol, ensure one of them is set. */
2538 {
2543 }
2548 }
2550 /* Add a symbol at the start of the glink branch table. */
2559 s++;
2560 count++;
2563 {
2564 /* Add a symbol for the glink PLT resolver. */
2573 s++;
2574 count++;
2575 }
2578 }
2579 \f
2580 /* The following functions are specific to the ELF linker, while
2581 functions above are used generally. They appear in this file more
2582 or less in the order in which they are called. eg.
2583 ppc_elf_check_relocs is called early in the link process,
2584 ppc_elf_finish_dynamic_sections is one of the last functions
2585 called. */
2587 /* The PPC linker needs to keep track of the number of relocs that it
2588 decides to copy as dynamic relocs in check_relocs for each symbol.
2589 This is so that it can later discard them if they are found to be
2590 unnecessary. We store the information in a field extending the
2591 regular ELF linker hash table. */
2593 struct ppc_elf_dyn_relocs
2594 {
2597 /* The input section of the reloc. */
2600 /* Total number of relocs copied for the input section. */
2601 bfd_size_type count;
2603 /* Number of pc-relative relocs copied for the input section. */
2604 bfd_size_type pc_count;
2605 };
2607 /* Track PLT entries needed for a given symbol. We might need more
2608 than one glink entry per symbol when generating a pic binary. */
2609 struct plt_entry
2610 {
2613 /* -fPIC uses multiple GOT sections, one per file, called ".got2".
2614 This field stores the offset into .got2 used to initialise the
2615 GOT pointer reg. It will always be at least 32768. (Current
2616 gcc always uses an offset of 32768, but ld -r will pack .got2
2617 sections together resulting in larger offsets). */
2618 bfd_vma addend;
2620 /* The .got2 section. */
2623 /* PLT refcount or offset. */
2624 union
2625 {
2626 bfd_signed_vma refcount;
2627 bfd_vma offset;
2630 /* .glink stub offset. */
2631 bfd_vma glink_offset;
2632 };
2634 /* Of those relocs that might be copied as dynamic relocs, this function
2635 selects those that must be copied when linking a shared library,
2636 even when the symbol is local. */
2638 static int
2641 {
2643 {
2660 }
2661 }
2663 /* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
2664 copying dynamic variables from a shared lib into an app's dynbss
2665 section, and instead use a dynamic relocation to point into the
2666 shared lib. */
2667 #define ELIMINATE_COPY_RELOCS 1
2669 /* PPC ELF linker hash entry. */
2671 struct ppc_elf_link_hash_entry
2672 {
2675 /* If this symbol is used in the linker created sections, the processor
2676 specific backend uses this field to map the field into the offset
2677 from the beginning of the section. */
2680 /* Track dynamic relocs copied for this symbol. */
2683 /* Contexts in which symbol is used in the GOT (or TOC).
2684 TLS_GD .. TLS_TLS bits are or'd into the mask as the
2685 corresponding relocs are encountered during check_relocs.
2686 tls_optimize clears TLS_GD .. TLS_TPREL when optimizing to
2687 indicate the corresponding GOT entry type is not needed. */
2697 /* Nonzero if we have seen a small data relocation referring to this
2698 symbol. */
2700 };
2702 #define ppc_elf_hash_entry(ent) ((struct ppc_elf_link_hash_entry *) (ent))
2704 /* PPC ELF linker hash table. */
2706 struct ppc_elf_link_hash_table
2707 {
2710 /* Short-cuts to get to dynamic linker sections. */
2725 /* The (unloaded but important) .rela.plt.unloaded on VxWorks. */
2728 /* The .got.plt section (VxWorks only)*/
2731 /* Shortcut to __tls_get_addr. */
2734 /* The bfd that forced an old-style PLT. */
2737 /* TLS local dynamic got entry handling. */
2739 bfd_signed_vma refcount;
2740 bfd_vma offset;
2743 /* Offset of branch table to PltResolve function in glink. */
2744 bfd_vma glink_pltresolve;
2746 /* Size of reserved GOT entries. */
2748 /* Non-zero if allocating the header left a gap. */
2751 /* The type of PLT we have chosen to use. */
2754 /* Set if we should emit symbols for stubs. */
2757 /* True if the target system is VxWorks. */
2760 /* The size of PLT entries. */
2762 /* The distance between adjacent PLT slots. */
2764 /* The size of the first PLT entry. */
2767 /* Small local sym cache. */
2769 };
2771 /* Get the PPC ELF linker hash table from a link_info structure. */
2773 #define ppc_elf_hash_table(p) \
2774 ((struct ppc_elf_link_hash_table *) (p)->hash)
2776 /* Create an entry in a PPC ELF linker hash table. */
2782 {
2783 /* Allocate the structure if it has not already been allocated by a
2784 subclass. */
2786 {
2791 }
2793 /* Call the allocation method of the superclass. */
2796 {
2800 }
2803 }
2805 /* Create a PPC ELF linker hash table. */
2809 {
2817 ppc_elf_link_hash_newfunc,
2819 {
2822 }
2842 }
2844 /* Create .got and the related sections. */
2846 static bfd_boolean
2848 {
2851 flagword flags;
2862 {
2866 }
2867 else
2868 {
2869 /* The powerpc .got has a blrl instruction in it. Mark it
2870 executable. */
2875 }
2882 }
2884 static bfd_boolean
2886 {
2889 flagword flags;
2914 }
2916 /* We have to create .dynsbss and .rela.sbss here so that they get mapped
2917 to output sections (just like _bfd_elf_create_dynamic_sections has
2918 to create .dynbss and .rela.bss). */
2920 static bfd_boolean
2922 {
2925 flagword flags;
2948 {
2957 }
2970 /* The VxWorks PLT is a loaded section with contents. */
2973 }
2975 /* Copy the extra info we tack onto an elf_link_hash_entry. */
2977 static void
2981 {
2988 {
2990 {
2994 /* Add reloc counts against the indirect sym to the direct sym
2995 list. Merge any entries against the same section. */
2997 {
3002 {
3007 }
3010 }
3012 }
3016 }
3021 /* If called to transfer flags for a weakdef during processing
3022 of elf_adjust_dynamic_symbol, don't copy non_got_ref.
3023 We clear it ourselves for ELIMINATE_COPY_RELOCS. */
3035 /* If we were called to copy over info for a weak sym, that's all. */
3039 /* Copy over the GOT refcount entries that we may have already seen to
3040 the symbol which just became indirect. */
3044 /* And plt entries. */
3046 {
3048 {
3053 {
3058 {
3062 }
3065 }
3067 }
3071 }
3074 {
3082 }
3083 }
3085 /* Hook called by the linker routine which adds symbols from an object
3086 file. We use it to put .comm items in .sbss, and not .bss. */
3088 static bfd_boolean
3096 {
3101 {
3102 /* Common symbols less than or equal to -G nn bytes are automatically
3103 put into .sbss. */
3108 {
3116 flags);
3119 }
3123 }
3129 }
3130 \f
3131 static bfd_boolean
3134 {
3143 }
3145 /* Create a special linker section. */
3147 static bfd_boolean
3150 flagword flags,
3152 {
3159 /* Record the first bfd that needs the special sections. */
3165 flags);
3172 }
3174 /* Find a linker generated pointer with a given addend and type. */
3177 elf_find_pointer_linker_section
3179 bfd_vma addend,
3181 {
3187 }
3189 /* Allocate a pointer to live in a linker created section. */
3191 static bfd_boolean
3196 {
3200 bfd_size_type amt;
3204 /* Is this a global symbol? */
3206 {
3209 /* Has this symbol already been allocated? If so, our work is done. */
3213 lsect))
3217 }
3218 else
3219 {
3222 /* Allocation of a pointer to a local symbol. */
3225 /* Allocate a table to hold the local symbols if first time. */
3227 {
3238 }
3240 /* Has this symbol already been allocated? If so, our work is done. */
3243 lsect))
3247 }
3249 /* Allocate space for a pointer in the linker section, and allocate
3250 a new pointer record from internal memory. */
3266 #ifdef DEBUG
3271 #endif
3274 }
3281 {
3287 {
3297 }
3305 }
3307 static bfd_boolean
3310 {
3317 {
3327 }
3330 }
3334 {
3343 }
3345 static bfd_boolean
3347 {
3358 }
3360 static void
3362 {
3365 abfd,
3368 }
3370 /* Look through the relocs for a section during the first phase, and
3371 allocate space in the global offset table or procedure linkage
3372 table. */
3374 static bfd_boolean
3379 {
3391 /* Don't do anything special with non-loaded, non-alloced sections.
3392 In particular, any relocs in such sections should not affect GOT
3393 and PLT reference counting (ie. we don't allow them to create GOT
3394 or PLT entries), there's no possibility or desire to optimize TLS
3395 relocs, and there's not much point in propagating relocs to shared
3396 libs that the dynamic linker won't relocate. */
3400 #ifdef DEBUG
3403 #endif
3407 /* Initialize howto table if not already done. */
3413 {
3418 }
3428 {
3438 else
3439 {
3444 }
3446 /* If a relocation refers to _GLOBAL_OFFSET_TABLE_, create the .got.
3447 This shows up in particular in an R_PPC_ADDR32 in the eabi
3448 startup code. */
3452 {
3458 }
3464 {
3466 {
3469 }
3470 else
3471 {
3480 {
3481 bfd_vma addend;
3484 PLT_IFUNC);
3488 /* STT_GNU_IFUNC symbols must have a PLT entry;
3489 In a non-pie executable even when there are
3490 no plt calls. */
3493 {
3497 }
3501 }
3502 }
3503 }
3509 {
3513 /* We have a new-style __tls_get_addr call with a marker
3514 reloc. */
3515 ;
3516 else
3517 /* Mark this section as having an old-style call. */
3519 }
3522 {
3525 /* These special tls relocs tie a call to __tls_get_addr with
3526 its parameter symbol. */
3557 dogottls:
3559 /* Fall thru */
3561 /* GOT16 relocations */
3566 /* This symbol requires a global offset table entry. */
3568 {
3573 }
3575 {
3578 }
3579 else
3580 /* This is a global offset table entry for a local symbol. */
3584 /* We may also need a plt entry if the symbol turns out to be
3585 an ifunc. */
3587 {
3590 }
3593 /* Indirect .sdata relocation. */
3596 {
3599 }
3608 {
3611 }
3614 /* Indirect .sdata2 relocation. */
3617 {
3620 }
3629 {
3632 }
3637 {
3640 }
3645 {
3648 }
3653 {
3656 }
3661 {
3664 }
3670 {
3673 }
3681 {
3684 }
3693 {
3696 }
3704 /* Fall through */
3710 #ifdef DEBUG
3712 #endif
3713 /* This symbol requires a procedure linkage table entry. We
3714 actually build the entry in finish_dynamic_symbol,
3715 because this might be a case of linking PIC code without
3716 linking in any dynamic objects, in which case we don't
3717 need to generate a procedure linkage table after all. */
3720 {
3721 /* It does not make sense to have a procedure linkage
3722 table entry for a local symbol. */
3725 abfd,
3726 sec,
3731 }
3732 else
3733 {
3737 {
3741 }
3746 }
3749 /* The following relocations don't need to propagate the
3750 relocation if linking a shared object since they are
3751 section relative. */
3770 /* These are just markers. */
3781 /* These should only appear in dynamic objects. */
3789 /* These aren't handled yet. We'll report an error later. */
3798 /* This refers only to functions defined in the shared library. */
3801 {
3804 }
3807 /* This relocation describes the C++ object vtable hierarchy.
3808 Reconstruct it for later use during GC. */
3814 /* This relocation describes which C++ vtable entries are actually
3815 used. Record for later use during GC. */
3823 /* We shouldn't really be seeing these. */
3833 /* Nor these. */
3844 {
3845 /* Old -fPIC gcc code has .long LCTOC1-LCFx just before
3846 the start of a function, which assembles to a REL32
3847 reference to .got2. If we detect one of these, then
3848 force the old PLT layout because the linker cannot
3849 reliably deduce the GOT pointer value needed for
3850 PLT call stubs. */
3861 {
3864 }
3865 }
3868 /* fall through */
3878 {
3879 /* We may need a plt entry if the symbol turns out to be
3880 a function defined in a dynamic object. */
3884 /* We may need a copy reloc too. */
3887 }
3897 {
3899 {
3902 }
3904 }
3905 /* fall through */
3912 {
3913 /* We may need a plt entry if the symbol turns out to be
3914 a function defined in a dynamic object. */
3919 }
3921 dodyn:
3922 /* If we are creating a shared library, and this is a reloc
3923 against a global symbol, or a non PC relative reloc
3924 against a local symbol, then we need to copy the reloc
3925 into the shared library. However, if we are linking with
3926 -Bsymbolic, we do not need to copy a reloc against a
3927 global symbol which is defined in an object we are
3928 including in the link (i.e., DEF_REGULAR is set). At
3929 this point we have not seen all the input files, so it is
3930 possible that DEF_REGULAR is not set now but will be set
3931 later (it is never cleared). In case of a weak definition,
3932 DEF_REGULAR may be cleared later by a strong definition in
3933 a shared library. We account for that possibility below by
3934 storing information in the dyn_relocs field of the hash
3935 table entry. A similar situation occurs when creating
3936 shared libraries and symbol visibility changes render the
3937 symbol local.
3939 If on the other hand, we are creating an executable, we
3940 may need to keep relocations for symbols satisfied by a
3941 dynamic library if we manage to avoid copy relocs for the
3942 symbol. */
3949 || (ELIMINATE_COPY_RELOCS
3954 {
3958 #ifdef DEBUG
3960 "ppc_elf_check_relocs needs to "
3964 #endif
3966 {
3970 sreloc = _bfd_elf_make_dynamic_reloc_section
3975 }
3977 /* If this is a global symbol, we count the number of
3978 relocations we need for this symbol. */
3980 {
3982 }
3983 else
3984 {
3985 /* Track dynamic relocs needed for local syms too.
3986 We really need local syms available to do this
3987 easily. Oh well. */
4003 }
4007 {
4016 }
4021 }
4024 }
4025 }
4028 }
4029 \f
4031 /* Merge object attributes from IBFD into OBFD. Raise an error if
4032 there are conflicting attributes. */
4033 static bfd_boolean
4035 {
4040 {
4041 /* This is the first object. Copy the attributes. */
4044 /* Use the Tag_null value to indicate the attributes have been
4045 initialized. */
4049 }
4054 /* Check for conflicting Tag_GNU_Power_ABI_FP attributes and merge
4055 non-conflicting ones. */
4059 {
4064 ;
4066 _bfd_error_handler
4069 _bfd_error_handler
4073 _bfd_error_handler
4077 _bfd_error_handler
4081 _bfd_error_handler
4084 _bfd_error_handler
4087 else
4088 _bfd_error_handler
4091 }
4093 /* Check for conflicting Tag_GNU_Power_ABI_Vector attributes and
4094 merge non-conflicting ones. */
4098 {
4102 {
4106 }
4109 {
4113 }
4119 ;
4120 /* For now, allow generic to transition to AltiVec or SPE
4121 without a warning. If GCC marked files with their stack
4122 alignment and used don't-care markings for files which are
4123 not affected by the vector ABI, we could warn about this
4124 case too. */
4128 ;
4130 _bfd_error_handler
4134 _bfd_error_handler
4137 else
4138 _bfd_error_handler
4141 }
4143 /* Check for conflicting Tag_GNU_Power_ABI_Struct_Return attributes
4144 and merge non-conflicting ones. */
4148 {
4153 ;
4155 _bfd_error_handler
4158 _bfd_error_handler
4161 _bfd_error_handler
4164 else
4165 _bfd_error_handler
4168 }
4170 /* Merge Tag_compatibility attributes and any common GNU ones. */
4174 }
4176 /* Merge backend specific data from an object file to the output
4177 object file when linking. */
4179 static bfd_boolean
4181 {
4182 flagword old_flags;
4183 flagword new_flags;
4184 bfd_boolean error;
4189 /* Check if we have the same endianess. */
4199 {
4200 /* First call, no flags set. */
4203 }
4205 /* Compatible flags are ok. */
4207 ;
4209 /* Incompatible flags. */
4210 else
4211 {
4212 /* Warn about -mrelocatable mismatch. Allow -mrelocatable-lib
4213 to be linked with either. */
4217 {
4222 }
4225 {
4230 }
4232 /* The output is -mrelocatable-lib iff both the input files are. */
4236 /* The output is -mrelocatable iff it can't be -mrelocatable-lib,
4237 but each input file is either -mrelocatable or -mrelocatable-lib. */
4243 /* Do not warn about eabi vs. V.4 mismatch, just or in the bit if
4244 any module uses it. */
4250 /* Warn about any other mismatches. */
4252 {
4258 }
4261 {
4264 }
4265 }
4268 }
4269 \f
4270 /* Choose which PLT scheme to use, and set .plt flags appropriately.
4271 Returns -1 on error, 0 for old PLT, 1 for new PLT. */
4272 int
4277 {
4279 flagword flags;
4284 {
4287 else
4288 {
4292 /* Look through the reloc flags left by ppc_elf_check_relocs.
4293 Use the old style bss plt if a file makes plt calls
4294 without using the new relocs, and if ld isn't given
4295 --secure-plt and we never see REL16 relocs. */
4300 {
4304 {
4308 }
4309 }
4311 }
4312 }
4321 {
4325 /* The new PLT is a loaded section. */
4330 /* The new GOT is not executable. */
4334 }
4335 else
4336 {
4337 /* Stop an unused .glink section from affecting .text alignment. */
4341 }
4343 }
4344 \f
4345 /* Return the section that should be marked against GC for a given
4346 relocation. */
4354 {
4357 {
4361 }
4364 }
4366 /* Update the got, plt and dynamic reloc reference counts for the
4367 section being removed. */
4369 static bfd_boolean
4374 {
4398 {
4405 {
4417 {
4418 /* Everything must go for SEC. */
4421 }
4422 }
4430 {
4436 {
4447 }
4448 }
4451 {
4473 {
4477 {
4483 }
4484 }
4486 {
4489 }
4499 /* Fall thru */
4522 {
4531 }
4536 }
4537 }
4539 }
4540 \f
4541 /* Set plt output section type, htab->tls_get_addr, and call the
4542 generic ELF tls_setup function. */
4544 asection *
4546 {
4553 {
4556 }
4561 }
4563 /* Return TRUE iff REL is a branch reloc with a global symbol matching
4564 HASH. */
4566 static bfd_boolean
4570 {
4576 {
4586 }
4588 }
4590 /* Run through all the TLS relocs looking for optimization
4591 opportunities. */
4593 bfd_boolean
4596 {
4606 /* Make two passes through the relocs. First time check that tls
4607 relocs involved in setting up a tls_get_addr call are indeed
4608 followed by such a call. If they are not, exclude them from
4609 the optimizations done on the second pass. */
4612 {
4618 {
4621 /* Read the relocations. */
4629 {
4635 bfd_boolean is_local;
4641 {
4649 }
4659 {
4663 /* Fall thru */
4667 /* These relocs should never be against a symbol
4668 defined in a shared lib. Leave them alone if
4669 that turns out to be the case. */
4673 /* LD -> LE */
4681 /* Fall thru */
4686 /* GD -> LE */
4688 else
4689 /* GD -> IE */
4699 {
4700 /* IE -> LE */
4704 }
4705 else
4710 }
4713 {
4723 /* Uh oh, we didn't find the expected call. We
4724 could just mark this symbol to exclude it
4725 from tls optimization but it's safer to skip
4726 the entire section. */
4729 }
4732 {
4735 }
4736 else
4737 {
4744 {
4751 {
4755 }
4756 }
4766 }
4769 {
4770 /* We managed to get rid of a got entry. */
4773 }
4776 {
4783 }
4787 }
4791 }
4795 {
4798 else
4800 }
4801 }
4803 }
4804 \f
4805 /* Return true if we have dynamic relocs that apply to read-only sections. */
4807 static bfd_boolean
4809 {
4813 {
4820 }
4822 }
4824 /* Adjust a symbol defined by a dynamic object and referenced by a
4825 regular object. The current definition is in some section of the
4826 dynamic object, but we're not including those sections. We have to
4827 change the definition to something the rest of the link can
4828 understand. */
4830 static bfd_boolean
4833 {
4837 #ifdef DEBUG
4840 #endif
4842 /* Make sure we know what is going on here. */
4852 /* Deal with function syms. */
4856 {
4857 /* Clear procedure linkage table information for any symbol that
4858 won't need a .plt entry. */
4868 {
4869 /* A PLT entry is not required/allowed when:
4871 1. We are not using ld.so; because then the PLT entry
4872 can't be set up, so we can't use one. In this case,
4873 ppc_elf_adjust_dynamic_symbol won't even be called.
4875 2. GC has rendered the entry unused.
4877 3. We know for certain that a call to this symbol
4878 will go to this object, or will remain undefined. */
4881 }
4882 else
4883 {
4884 /* After adjust_dynamic_symbol, non_got_ref set in the
4885 non-shared case means that we have allocated space in
4886 .dynbss for the symbol and thus dyn_relocs for this
4887 symbol should be discarded.
4888 If we get here we know we are making a PLT entry for this
4889 symbol, and in an executable we'd normally resolve
4890 relocations against this symbol to the PLT entry. Allow
4891 dynamic relocs if the reference is weak, and the dynamic
4892 relocs will not cause text relocation. */
4900 }
4902 }
4903 else
4906 /* If this is a weak symbol, and there is a real definition, the
4907 processor independent code will have arranged for us to see the
4908 real definition first, and we can just use the same value. */
4910 {
4918 }
4920 /* This is a reference to a symbol defined by a dynamic object which
4921 is not a function. */
4923 /* If we are creating a shared library, we must presume that the
4924 only references to the symbol are via the global offset table.
4925 For such cases we need not do anything here; the relocations will
4926 be handled correctly by relocate_section. */
4930 /* If there are no references to this symbol that do not use the
4931 GOT, we don't need to generate a copy reloc. */
4935 /* If we didn't find any dynamic relocs in read-only sections, then
4936 we'll be keeping the dynamic relocs and avoiding the copy reloc.
4937 We can't do this if there are any small data relocations. This
4938 doesn't work on VxWorks, where we can not have dynamic
4939 relocations (other than copy and jump slot relocations) in an
4940 executable. */
4946 {
4949 }
4952 {
4956 }
4958 /* We must allocate the symbol in our .dynbss section, which will
4959 become part of the .bss section of the executable. There will be
4960 an entry for this symbol in the .dynsym section. The dynamic
4961 object will contain position independent code, so all references
4962 from the dynamic object to this symbol will go through the global
4963 offset table. The dynamic linker will use the .dynsym entry to
4964 determine the address it must put in the global offset table, so
4965 both the dynamic object and the regular object will refer to the
4966 same memory location for the variable.
4968 Of course, if the symbol is referenced using SDAREL relocs, we
4969 must instead allocate it in .sbss. */
4973 else
4977 /* We must generate a R_PPC_COPY reloc to tell the dynamic linker to
4978 copy the initial value out of the dynamic object and into the
4979 runtime process image. We need to remember the offset into the
4980 .rela.bss section we are going to use. */
4982 {
4987 else
4992 }
4995 }
4996 \f
4997 /* Generate a symbol to mark plt call stubs. For non-PIC code the sym is
4998 xxxxxxxx.plt_call32.<callee> where xxxxxxxx is a hex number, usually 0,
4999 specifying the addend on the plt relocation. For -fpic code, the sym
5000 is xxxxxxxx.plt_pic32.<callee>, and for -fPIC
5001 xxxxxxxx.got2.plt_pic32.<callee>. */
5003 static bfd_boolean
5007 {
5016 else
5036 {
5045 }
5047 }
5049 /* Allocate NEED contiguous space in .got, and return the offset.
5050 Handles allocation of the got header when crossing 32k. */
5052 static bfd_vma
5054 {
5055 bfd_vma where;
5059 {
5062 }
5063 else
5064 {
5067 {
5070 }
5071 else
5072 {
5075 {
5078 }
5081 }
5082 }
5084 }
5086 /* Allocate space in associated reloc sections for dynamic relocs. */
5088 static bfd_boolean
5090 {
5100 /* When warning symbols are created, they **replace** the "real"
5101 entry in the hash table, thus we never get to see the real
5102 symbol in a hash traversal. So look at it now. */
5108 {
5112 bfd_boolean dyn;
5116 {
5117 /* Make sure this symbol is output as a dynamic symbol. */
5122 {
5125 }
5131 {
5137 {
5139 {
5142 }
5147 {
5150 }
5155 {
5158 }
5164 }
5165 else
5166 {
5168 {
5169 /* If this is the first .plt entry, make room
5170 for the special first entry. */
5174 /* The PowerPC PLT is actually composed of two
5175 parts, the first part is 2 words (for a load
5176 and a jump), and then there is a remaining
5177 word available at the end. */
5184 /* If this symbol is not defined in a regular
5185 file, and we are not generating a shared
5186 library, then set the symbol to this location
5187 in the .plt. This is to avoid text
5188 relocations, and is required to make
5189 function pointers compare as equal between
5190 the normal executable and the shared library. */
5194 {
5197 }
5199 /* Make room for this entry. */
5201 /* After the 8192nd entry, room for two entries
5202 is allocated. */
5208 }
5210 }
5212 /* We also need to make an entry in the .rela.plt section. */
5214 {
5218 else
5219 {
5223 {
5224 /* Allocate space for the unloaded relocations. */
5227 {
5230 {
5234 }
5239 }
5241 /* Every PLT entry has an associated GOT entry in
5242 .got.plt. */
5244 }
5245 }
5247 }
5248 }
5249 else
5251 }
5252 else
5256 {
5259 }
5260 }
5261 else
5262 {
5265 }
5269 {
5270 bfd_boolean dyn;
5273 /* Make sure this symbol is output as a dynamic symbol. */
5278 {
5281 }
5285 {
5287 {
5289 /* We'll just use htab->tlsld_got.offset. This should
5290 always be the case. It's a little odd if we have
5291 a local dynamic reloc against a non-local symbol. */
5293 else
5295 }
5302 }
5303 else
5307 else
5308 {
5315 {
5317 /* All the entries we allocated need relocs.
5318 Except LD only needs one. */
5323 }
5324 }
5325 }
5326 else
5333 /* In the shared -Bsymbolic case, discard space allocated for
5334 dynamic pc-relative relocs against symbols which turn out to be
5335 defined in regular objects. For the normal shared case, discard
5336 space for relocs that have become local due to symbol visibility
5337 changes. */
5340 {
5341 /* Relocs that use pc_count are those that appear on a call insn,
5342 or certain REL relocs (see must_be_dyn_reloc) that can be
5343 generated via assembly. We want calls to protected symbols to
5344 resolve directly to the function rather than going via the plt.
5345 If people want function pointer comparisons to work as expected
5346 then they should avoid writing weird assembly. */
5348 {
5352 {
5357 else
5359 }
5360 }
5363 {
5367 {
5370 else
5372 }
5373 }
5375 /* Discard relocs on undefined symbols that must be local. */
5382 /* Also discard relocs on undefined weak syms with non-default
5383 visibility. */
5386 {
5390 /* Make sure undefined weak symbols are output as a dynamic
5391 symbol in PIEs. */
5395 {
5398 }
5399 }
5400 }
5402 {
5403 /* For the non-shared case, discard space for relocs against
5404 symbols which turn out to need copy relocs or are not
5405 dynamic. */
5409 {
5410 /* Make sure this symbol is output as a dynamic symbol.
5411 Undefined weak syms won't yet be marked as dynamic. */
5414 {
5417 }
5419 /* If that succeeded, we know we'll be keeping all the
5420 relocs. */
5423 }
5427 keep: ;
5428 }
5430 /* Finally, allocate space. */
5432 {
5437 }
5440 }
5442 /* Set DF_TEXTREL if we find any dynamic relocs that apply to
5443 read-only sections. */
5445 static bfd_boolean
5447 {
5455 {
5458 /* Not an error, just cut short the traversal. */
5460 }
5462 }
5464 /* Set the sizes of the dynamic sections. */
5466 static bfd_boolean
5469 {
5472 bfd_boolean relocs;
5475 #ifdef DEBUG
5477 #endif
5483 {
5484 /* Set the contents of the .interp section to the interpreter. */
5486 {
5491 }
5492 }
5499 /* Set up .got offsets for local syms, and space for local dynamic
5500 relocs. */
5502 {
5508 bfd_size_type locsymcount;
5515 {
5522 {
5525 {
5526 /* Input section has been discarded, either because
5527 it is a copy of a linkonce section or due to
5528 linker script /DISCARD/, so we'll be discarding
5529 the relocs too. */
5530 }
5534 {
5535 /* Relocations in vxworks .tls_vars sections are
5536 handled specially by the loader. */
5537 }
5539 {
5548 }
5549 }
5550 }
5564 {
5567 {
5576 }
5577 else
5581 else
5582 {
5587 }
5588 }
5589 else
5595 /* Allocate space for calls to local STT_GNU_IFUNC syms in .iplt. */
5597 {
5604 {
5608 {
5611 }
5616 {
5619 }
5623 {
5626 }
5627 }
5628 else
5630 }
5631 }
5633 /* Allocate space for global sym dynamic relocs. */
5637 {
5641 }
5642 else
5646 {
5649 /* If we haven't allocated the header, do so now. When we get here,
5650 for old plt/got the got size will be 0 to 32764 (not allocated),
5651 or 32780 to 65536 (header allocated). For new plt/got, the
5652 corresponding ranges are 0 to 32768 and 32780 to 65536. */
5654 {
5659 }
5662 }
5667 {
5669 /* Space for the branch table. */
5671 /* Pad out to align the start of PLTresolve. */
5676 {
5683 {
5692 }
5698 {
5707 }
5708 }
5709 }
5711 /* We've now determined the sizes of the various dynamic sections.
5712 Allocate memory for them. */
5715 {
5723 {
5724 /* We'd like to strip these sections if they aren't needed, but if
5725 we've exported dynamic symbols from them we must leave them.
5726 It's too late to tell BFD to get rid of the symbols. */
5729 /* Strip this section if we don't need it; see the
5730 comment below. */
5731 }
5740 {
5741 /* Strip these too. */
5742 }
5744 {
5746 {
5747 /* Remember whether there are any relocation sections. */
5750 /* We use the reloc_count field as a counter if we need
5751 to copy relocs into the output file. */
5753 }
5754 }
5755 else
5756 {
5757 /* It's not one of our sections, so don't allocate space. */
5759 }
5762 {
5763 /* If we don't need this section, strip it from the
5764 output file. This is mostly to handle .rela.bss and
5765 .rela.plt. We must create both sections in
5766 create_dynamic_sections, because they must be created
5767 before the linker maps input sections to output
5768 sections. The linker does that before
5769 adjust_dynamic_symbol is called, and it is that
5770 function which decides whether anything needs to go
5771 into these sections. */
5774 }
5779 /* Allocate memory for the section contents. */
5783 }
5786 {
5787 /* Add some entries to the .dynamic section. We fill in the
5788 values later, in ppc_elf_finish_dynamic_sections, but we
5789 must add the entries now so that we get the correct size for
5790 the .dynamic section. The DT_DEBUG entry is filled in by the
5791 dynamic linker and used by the debugger. */
5792 #define add_dynamic_entry(TAG, VAL) \
5793 _bfd_elf_add_dynamic_entry (info, TAG, VAL)
5796 {
5799 }
5802 {
5808 }
5811 {
5814 }
5817 {
5822 }
5824 /* If any dynamic relocs apply to a read-only section, then we
5825 need a DT_TEXTREL entry. */
5828 info);
5831 {
5834 }
5838 }
5839 #undef add_dynamic_entry
5842 }
5844 /* Return TRUE if symbol should be hashed in the `.gnu.hash' section. */
5846 static bfd_boolean
5848 {
5856 }
5857 \f
5858 #define ARRAY_SIZE(a) (sizeof (a) / sizeof ((a)[0]))
5860 /* Relaxation trampolines. r12 is available for clobbering (r11, is
5861 used for some functions that are allowed to break the ABI). */
5863 {
5872 };
5875 {
5880 };
5882 static bfd_boolean
5887 {
5888 struct one_fixup
5889 {
5892 /* Final link, can use the symbol offset. For a
5893 relocatable link we use the symbol's index. */
5894 bfd_vma toff;
5895 bfd_vma trampoff;
5896 };
5906 bfd_size_type trampoff;
5911 /* Nothing to do if there are no relocations, and no need to do
5912 anything with non-alloc or non-code sections. */
5919 /* We cannot represent the required PIC relocs in the output, so don't
5920 do anything. The linker doesn't support mixing -shared and -r
5921 anyway. */
5926 /* Space for a branch around any trampolines. */
5931 /* Get a copy of the native relocations. */
5942 {
5956 {
5971 }
5973 /* Get the value of the symbol referred to by the reloc. */
5976 {
5977 /* A local symbol. */
5980 /* Read this BFD's local symbols. */
5982 {
5990 }
5998 else
6003 }
6004 else
6005 {
6006 /* Global symbol handling. */
6018 {
6021 }
6024 {
6027 }
6028 else
6032 }
6034 /* The condition here under which we call find_plt_ent must
6035 match that in relocate_section. If we call find_plt_ent here
6036 but not in relocate_section, or vice versa, then the branch
6037 destination used here may be incorrect. */
6040 {
6041 /* We know is_branch_reloc (r_type) is true. */
6045 }
6048 {
6053 }
6055 {
6063 {
6068 {
6071 }
6072 else
6073 {
6076 }
6077 }
6078 }
6080 /* If the branch and target are in the same section, you have
6081 no hope of adding stubs. We'll error out later should the
6082 branch overflow. */
6086 /* There probably isn't any reason to handle symbols in
6087 SEC_MERGE sections; SEC_MERGE doesn't seem a likely
6088 attribute for a code section, and we are only looking at
6089 branches. However, implement it correctly here as a
6090 reference for other target relax_section functions. */
6092 {
6093 /* At this stage in linking, no SEC_MERGE symbol has been
6094 adjusted, so all references to such symbols need to be
6095 passed through _bfd_merged_section_offset. (Later, in
6096 relocate_section, all SEC_MERGE symbols *except* for
6097 section symbols have been adjusted.)
6099 gas may reduce relocations against symbols in SEC_MERGE
6100 sections to a relocation against the section symbol when
6101 the original addend was zero. When the reloc is against
6102 a section symbol we should include the addend in the
6103 offset passed to _bfd_merged_section_offset, since the
6104 location of interest is the original symbol. On the
6105 other hand, an access to "sym+addend" where "sym" is not
6106 a section symbol should not include the addend; Such an
6107 access is presumed to be an offset from "sym"; The
6108 location of interest is just "sym". */
6114 toff);
6118 }
6119 /* PLTREL24 addends are special. */
6123 /* Attempted -shared link of non-pic code loses. */
6130 /* If the branch is in range, no need to do anything. */
6133 /* A relocatable link may have sections moved during
6134 final link, so do not presume they remain in range. */
6136 {
6143 }
6145 /* Look for an existing fixup to this address. */
6151 {
6157 /* Oh dear, we can't reach a trampoline. Don't try to add
6158 one. We'll report an error later. */
6162 {
6166 }
6167 else
6168 {
6172 }
6181 /* Hijack the old relocation. Since we need two
6182 relocations for this use a "composite" reloc. */
6184 stub_rtype);
6189 /* Record the fixup so we don't do it again this section. */
6198 changes++;
6199 }
6200 else
6201 {
6206 /* Nop out the reloc, since we're finalizing things here. */
6208 }
6210 /* Get the section contents. */
6212 {
6213 /* Get cached copy if it exists. */
6216 else
6217 {
6218 /* Go get them off disk. */
6221 }
6222 }
6224 /* Fix up the existing branch to hit the trampoline. */
6227 {
6245 }
6246 }
6248 /* Write out the trampolines. */
6250 {
6253 bfd_vma val;
6256 do
6257 {
6261 }
6269 /* Branch around the trampolines. */
6277 {
6280 }
6281 else
6282 {
6285 }
6289 {
6291 i++;
6295 }
6297 }
6301 {
6304 else
6305 {
6306 /* Cache the symbols for elf_link_input_bfd. */
6308 }
6309 }
6313 {
6316 else
6317 {
6318 /* Cache the section contents for elf_link_input_bfd. */
6320 }
6321 }
6324 {
6325 /* Append sufficient NOP relocs so we can write out relocation
6326 information for the trampolines. */
6336 {
6340 }
6347 }
6353 {
6354 /* Convert the internal relax relocs to external form. */
6357 {
6360 /* Rewrite the reloc and convert one of the trailing nop
6361 relocs to describe this relocation. */
6363 /* The relocs are at the bottom 2 bytes */
6369 irel++;
6370 }
6371 }
6375 error_return:
6385 }
6386 \f
6387 /* What to do when ld finds relocations against symbols defined in
6388 discarded sections. */
6390 static unsigned int
6392 {
6400 }
6401 \f
6402 /* Fill in the address for a pointer generated in a linker section. */
6404 static bfd_vma
6408 bfd_vma relocation,
6410 {
6416 {
6417 /* Handle global symbol. */
6423 }
6424 else
6425 {
6426 /* Handle local symbol. */
6432 }
6436 lsect);
6439 /* Offset will always be a multiple of four, so use the bottom bit
6440 as a "written" flag. */
6442 {
6447 }
6453 #ifdef DEBUG
6457 #endif
6459 /* Subtract out the addend, because it will get added back in by the normal
6460 processing. */
6462 }
6464 #define PPC_LO(v) ((v) & 0xffff)
6465 #define PPC_HI(v) (((v) >> 16) & 0xffff)
6466 #define PPC_HA(v) PPC_HI ((v) + 0x8000)
6468 static void
6471 {
6474 bfd_vma plt;
6483 {
6496 {
6505 }
6506 else
6507 {
6516 }
6517 }
6518 else
6519 {
6528 }
6529 }
6531 /* The RELOCATE_SECTION function is called by the ELF backend linker
6532 to handle the relocations for a section.
6534 The relocs are always passed as Rela structures; if the section
6535 actually uses Rel structures, the r_addend field will always be
6536 zero.
6538 This function is responsible for adjust the section contents as
6539 necessary, and (if using Rela relocs and generating a
6540 relocatable output file) adjusting the reloc addend as
6541 necessary.
6543 This function does not have to worry about setting the reloc
6544 address or the reloc symbol index.
6546 LOCAL_SYMS is a pointer to the swapped in local symbols.
6548 LOCAL_SECTIONS is an array giving the section in the input file
6549 corresponding to the st_shndx field of each local symbol.
6551 The global hash table entry for the global symbols can be found
6552 via elf_sym_hashes (input_bfd).
6554 When generating relocatable output, this function must handle
6555 STB_LOCAL/STT_SECTION symbols specially. The output symbol is
6556 going to be the section symbol corresponding to the output
6557 section, which means that the addend must be adjusted
6558 accordingly. */
6560 static bfd_boolean
6569 {
6575 Elf_Internal_Rela outrel;
6581 bfd_boolean is_vxworks_tls;
6583 #ifdef DEBUG
6589 #endif
6593 /* Initialize howto table if not already done. */
6601 /* We have to handle relocations in vxworks .tls_vars sections
6602 specially, because the dynamic loader is 'weird'. */
6609 {
6611 bfd_vma addend;
6612 bfd_reloc_status_type r;
6619 bfd_vma relocation;
6621 bfd_boolean unresolved_reloc;
6622 bfd_boolean warned;
6635 {
6641 }
6642 else
6643 {
6650 }
6653 {
6654 /* For relocs against symbols from removed linkonce sections,
6655 or sections discarded by a linker script, we just want the
6656 section contents zeroed. Avoid any special processing. */
6664 }
6667 {
6671 {
6672 /* R_PPC_PLTREL24 is rather special. If non-zero, the
6673 addend specifies the GOT pointer offset within .got2. */
6675 }
6677 }
6679 /* TLS optimizations. Replace instruction sequences and relocs
6680 based on information we collected in tls_optimize. We edit
6681 RELOCS so that --emit-relocs will output something sensible
6682 for the final instruction stream. */
6688 {
6691 local_plt
6695 }
6697 /* Ensure reloc mapping code below stays sane. */
6708 {
6716 {
6717 bfd_vma insn;
6724 }
6730 {
6739 else
6742 /* add -> addi. */
6748 /* load and store indexed -> dform. */
6752 /* ldx, ldux, stdx, stdux -> ld, ldu, std, stdu. */
6757 /* lwax -> lwa. */
6759 else
6766 /* Was PPC_TLS which sits on insn boundary, now
6767 PPC_TPREL16_LO which is at low-order half-word. */
6769 }
6782 {
6783 tls_gdld_hi:
6787 else
6788 {
6792 }
6794 }
6807 {
6809 bfd_vma offset;
6811 tls_ldgd_opt:
6813 /* If not using the newer R_PPC_TLSGD/LD to mark
6814 __tls_get_addr calls, we must trust that the call
6815 stays with its arg setup insns, ie. that the next
6816 reloc is the __tls_get_addr call associated with
6817 the current reloc. Edit both insns. */
6824 {
6825 /* IE */
6831 {
6834 R_PPC_NONE);
6837 }
6841 }
6842 else
6843 {
6844 /* LE */
6847 {
6848 /* Was an LD reloc. */
6851 r_symndx++)
6861 }
6865 {
6871 }
6872 }
6876 {
6877 /* We changed the symbol on an LD reloc. Start over
6878 in order to get h, sym, sec etc. right. */
6879 rel--;
6881 }
6882 }
6887 {
6892 {
6893 /* IE */
6896 }
6897 else
6898 {
6899 /* LE */
6903 }
6906 /* Zap the reloc on the _tls_get_addr call too. */
6909 R_PPC_NONE);
6910 }
6915 {
6920 r_symndx++)
6936 /* Zap the reloc on the _tls_get_addr call too. */
6939 R_PPC_NONE);
6940 rel--;
6942 }
6944 }
6946 /* Handle other relocations that tweak non-addend part of insn. */
6949 {
6953 /* Branch taken prediction relocations. */
6957 /* Fall thru */
6959 /* Branch not taken prediction relocations. */
6970 /* Invert 'y' bit if not the default. */
6976 }
6980 {
6984 {
6987 }
6990 {
6996 }
7002 {
7007 }
7009 {
7011 {
7012 Elf_Internal_Rela rela;
7026 }
7028 {
7031 }
7040 else
7044 }
7045 }
7053 {
7072 /* GOT16 relocations. Like an ADDR16 using the symbol's
7073 address in the GOT as relocation value instead of the
7074 symbol's value itself. Also, create a GOT entry for the
7075 symbol and put the symbol value there. */
7109 dogot:
7110 {
7111 /* Relocation is to the entry for this symbol in the global
7112 offset table. */
7113 bfd_vma off;
7126 {
7127 bfd_boolean dyn;
7132 /* This is actually a static link, or it is a
7133 -Bsymbolic link and the symbol is defined
7134 locally, or the symbol was forced to be local
7135 because of a version file. */
7136 ;
7137 else
7138 {
7141 }
7143 }
7144 else
7145 {
7149 }
7151 /* The offset must always be a multiple of 4. We use the
7152 least significant bit to record whether we have already
7153 processed this entry. */
7157 else
7158 {
7169 /* We might have multiple got entries for this sym.
7170 Initialize them all. */
7171 do
7172 {
7176 {
7179 }
7181 {
7184 }
7186 {
7189 }
7191 {
7194 }
7196 /* Generate relocs for the dynamic linker. */
7202 {
7210 {
7213 {
7220 outrel.r_info
7222 }
7223 }
7232 else
7235 {
7239 }
7244 }
7246 /* Init the .got section contents if we're not
7247 emitting a reloc. */
7248 else
7249 {
7255 {
7261 {
7265 }
7266 }
7269 }
7274 }
7279 }
7285 {
7287 {
7293 {
7297 {
7300 }
7301 }
7302 }
7303 }
7307 + off
7310 /* Addends on got relocations don't make much sense.
7311 x+off@got is actually x@got+off, and since the got is
7312 generated by a hash table traversal, the value in the
7313 got at entry m+n bears little relation to the entry m. */
7317 input_bfd,
7318 input_section,
7321 sym_name);
7322 }
7325 /* Relocations that need no special processing. */
7327 /* It makes no sense to point a local relocation
7328 at a symbol not in this object. */
7330 {
7333 input_bfd,
7334 input_section,
7336 TRUE))
7339 }
7349 /* Relocations that may need to be propagated if this is a shared
7350 object. */
7356 /* The TPREL16 relocs shouldn't really be used in shared
7357 libs as they will result in DT_TEXTREL being set, but
7358 support them anyway. */
7383 /* fall through */
7398 /* If these relocations are not to a named symbol, they can be
7399 handled right here, no need to bother the dynamic linker. */
7403 /* fall through */
7411 /* fall through */
7413 dodyn:
7427 || (ELIMINATE_COPY_RELOCS
7433 {
7436 #ifdef DEBUG
7441 #endif
7443 /* When generating a shared object, these relocations
7444 are copied into the output file to be resolved at run
7445 time. */
7447 {
7453 }
7471 {
7475 }
7476 else
7477 {
7481 {
7485 {
7486 /* If we get here when building a static
7487 executable, then the libc startup function
7488 responsible for applying indirect function
7489 relocations is going to complain about
7490 the reloc type.
7491 If we get here when building a dynamic
7492 executable, it will be because we have
7493 a text relocation. The dynamic loader
7494 will set the text segment writable and
7495 non-executable to apply text relocations.
7496 So we'll segfault when trying to run the
7497 indirection function to resolve the reloc. */
7501 input_bfd,
7502 input_section,
7505 sym_name);
7507 }
7509 ;
7511 {
7514 }
7515 else
7516 {
7519 /* We are turning this relocation into one
7520 against a section symbol. It would be
7521 proper to subtract the symbol's value,
7522 osec->vma, from the emitted reloc addend,
7523 but ld.so expects buggy relocs.
7524 FIXME: Why not always use a zero index? */
7528 {
7531 }
7533 #ifdef DEBUG
7538 #endif
7539 }
7542 }
7545 else
7547 }
7556 /* This reloc will be computed at runtime. We clear the memory
7557 so that it contains predictable value. */
7561 {
7565 }
7566 }
7572 {
7579 else
7583 }
7586 /* Fall thru */
7592 /* Fall thru */
7595 relax32:
7596 {
7603 /* We're clearing the bits for R_PPC_ADDR16_HA
7604 and R_PPC_ADDR16_LO here. */
7608 /* t0 is HA, t1 is LO */
7616 /* Rewrite the reloc and convert one of the trailing nop
7617 relocs to describe this relocation. */
7619 /* The relocs are at the bottom 2 bytes */
7625 rel++;
7626 }
7629 /* Indirect .sdata relocation. */
7632 relocation
7637 /* Indirect .sdata2 relocation. */
7640 relocation
7645 /* Handle the TOC16 reloc. We want to use the offset within the .got
7646 section, not the actual VMA. This is appropriate when generating
7647 an embedded ELF object, for which the .got section acts like the
7648 AIX .toc section. */
7651 {
7654 }
7664 /* Relocation is to the entry for this symbol in the
7665 procedure linkage table. */
7666 {
7672 {
7673 /* We didn't make a PLT entry for this symbol. This
7674 happens when statically linking PIC code, or when
7675 using -Bsymbolic. */
7677 }
7684 else
7688 }
7691 /* Relocate against _SDA_BASE_. */
7693 {
7697 {
7700 }
7707 {
7711 input_bfd,
7712 sym_name,
7714 name);
7715 }
7717 }
7720 /* Relocate against _SDA2_BASE_. */
7722 {
7726 {
7729 }
7734 {
7738 input_bfd,
7739 sym_name,
7741 name);
7746 }
7748 }
7751 /* Relocate against either _SDA_BASE_, _SDA2_BASE_, or 0. */
7754 {
7759 {
7762 }
7769 {
7772 }
7775 {
7778 }
7781 {
7783 }
7784 else
7785 {
7789 input_bfd,
7790 sym_name,
7792 name);
7797 }
7804 }
7805 }
7808 /* Relocate against the beginning of the section. */
7814 {
7817 }
7821 /* Negative relocations. */
7848 input_bfd,
7850 sym_name);
7855 }
7857 /* Do any further special processing. */
7859 {
7870 /* It's just possible that this symbol is a weak symbol
7871 that's not actually defined anywhere. In that case,
7872 'sec' would be NULL, and we should leave the symbol
7873 alone (it will be set to zero elsewhere in the link). */
7876 /* Fall thru */
7884 /* Add 0x10000 if sign bit in 0:15 is set.
7885 Bits 0:15 are not used. */
7888 }
7890 #ifdef DEBUG
7895 sym_name,
7896 r_symndx,
7899 #endif
7904 {
7907 input_bfd,
7908 input_section,
7911 sym_name);
7913 }
7916 input_bfd,
7917 input_section,
7918 contents,
7920 relocation,
7921 addend);
7924 {
7926 {
7932 {
7933 /* Assume this is a call protected by other code that
7934 detect the symbol is undefined. If this is the case,
7935 we can safely ignore the overflow. If not, the
7936 program is hosed anyway, and a little warning isn't
7937 going to help. */
7940 }
7944 sym_name,
7947 input_bfd,
7948 input_section,
7951 }
7952 else
7953 {
7959 }
7960 }
7961 }
7963 #ifdef DEBUG
7965 #endif
7968 }
7969 \f
7970 /* Finish up dynamic symbol handling. We set the contents of various
7971 dynamic sections here. */
7973 static bfd_boolean
7978 {
7981 bfd_boolean doneone;
7983 #ifdef DEBUG
7986 #endif
7994 {
7996 {
7997 Elf_Internal_Rela rela;
7999 bfd_vma reloc_index;
8005 else
8006 {
8012 }
8014 /* This symbol has an entry in the procedure linkage table.
8015 Set it up. */
8019 {
8020 bfd_vma got_offset;
8023 /* The first three entries in .got.plt are reserved. */
8026 /* Use the right PLT. */
8030 /* Fill in the .plt on VxWorks. */
8032 {
8039 }
8040 else
8041 {
8050 }
8057 /* This instruction is an immediate load. The value loaded is
8058 the byte offset of the R_PPC_JMP_SLOT relocation from the
8059 start of the .rela.plt section. The value is stored in the
8060 low-order 16 bits of the load instruction. */
8061 /* NOTE: It appears that this is now an index rather than a
8062 prescaled offset. */
8066 /* This instruction is a PC-relative branch whose target is
8067 the start of the PLT section. The address of this branch
8068 instruction is 20 bytes beyond the start of this PLT entry.
8069 The address is encoded in bits 6-29, inclusive. The value
8070 stored is right-shifted by two bits, permitting a 26-bit
8071 offset. */
8081 /* Fill in the GOT entry corresponding to this PLT slot with
8082 the address immediately after the the "bctr" instruction
8083 in this PLT entry. */
8090 {
8091 /* Fill in a couple of entries in .rela.plt.unloaded. */
8097 /* Provide the @ha relocation for the first instruction. */
8102 R_PPC_ADDR16_HA);
8107 /* Provide the @l relocation for the second instruction. */
8112 R_PPC_ADDR16_LO);
8117 /* Provide a relocation for the GOT entry corresponding to this
8118 PLT slot. Point it at the middle of the .plt entry. */
8123 R_PPC_ADDR32);
8126 }
8128 /* VxWorks uses non-standard semantics for R_PPC_JMP_SLOT.
8129 In particular, the offset for the relocation is not the
8130 address of the PLT entry for this function, as specified
8131 by the ABI. Instead, the offset is set to the address of
8132 the GOT slot for this function. See EABI 4.4.4.1. */
8137 }
8138 else
8139 {
8151 {
8152 /* We don't need to fill in the .plt. The ppc dynamic
8153 linker will fill it in. */
8154 }
8155 else
8156 {
8162 }
8163 }
8165 /* Fill in the entry in the .rela.plt section. */
8169 {
8176 }
8177 else
8185 else
8191 {
8192 /* Mark the symbol as undefined, rather than as
8193 defined in the .plt section. Leave the value if
8194 there were any relocations where pointer equality
8195 matters (this is a clue for the dynamic linker, to
8196 make function pointer comparisons work between an
8197 application and shared library), otherwise set it
8198 to zero. */
8203 {
8204 /* This breaks function pointer comparisons, but
8205 that is better than breaking tests for a NULL
8206 function pointer. */
8208 }
8209 }
8212 {
8213 /* Set the value of ifunc symbols in a non-pie
8214 executable to the glink entry. This is to avoid
8215 text relocations. We can't do this for ifunc in
8216 allocate_dynrelocs, as we do for normal dynamic
8217 function symbols with plt entries, because we need
8218 to keep the original value around for the ifunc
8219 relocation. */
8225 }
8227 }
8232 {
8241 /* We only need one non-PIC glink stub. */
8243 }
8244 else
8246 }
8249 {
8251 Elf_Internal_Rela rela;
8254 /* This symbols needs a copy reloc. Set it up. */
8256 #ifdef DEBUG
8258 #endif
8264 else
8273 }
8275 #ifdef DEBUG
8277 #endif
8279 /* Mark some specially defined symbols as absolute. */
8288 }
8289 \f
8290 static enum elf_reloc_type_class
8292 {
8294 {
8305 }
8306 }
8307 \f
8308 /* Finish up the dynamic sections. */
8310 static bfd_boolean
8313 {
8317 bfd_vma got;
8321 #ifdef DEBUG
8323 #endif
8330 else
8338 {
8346 {
8347 Elf_Internal_Dyn dyn;
8353 {
8357 else
8377 {
8381 }
8389 }
8392 }
8393 }
8396 {
8399 {
8404 {
8405 /* Add a blrl instruction at _GLOBAL_OFFSET_TABLE_-4
8406 so that a function can easily find the address of
8407 _GLOBAL_OFFSET_TABLE_. */
8411 }
8414 {
8419 }
8420 }
8421 else
8422 {
8429 }
8432 }
8434 /* Fill in the first entry in the VxWorks procedure linkage table. */
8436 {
8437 /* Use the right PLT. */
8443 {
8450 }
8451 else
8452 {
8455 }
8464 {
8465 Elf_Internal_Rela rela;
8470 /* Output the @ha relocation for the first instruction. */
8479 /* Output the @l relocation for the second instruction. */
8488 /* Fix up the remaining relocations. They may have the wrong
8489 symbol index for _G_O_T_ or _P_L_T_ depending on the order
8490 in which symbols were output. */
8492 {
8493 Elf_Internal_Rela rel;
8509 }
8510 }
8511 }
8516 {
8519 bfd_vma res0;
8522 /*
8523 * PIC glink code is the following:
8524 *
8525 * # ith PLT code stub.
8526 * addis 11,30,(plt+(i-1)*4-got)@ha
8527 * lwz 11,(plt+(i-1)*4-got)@l(11)
8528 * mtctr 11
8529 * bctr
8530 *
8531 * # A table of branches, one for each plt entry.
8532 * # The idea is that the plt call stub loads ctr and r11 with these
8533 * # addresses, so (r11 - res_0) gives the plt index * 4.
8534 * res_0: b PLTresolve
8535 * res_1: b PLTresolve
8536 * .
8537 * # Some number of entries towards the end can be nops
8538 * res_n_m3: nop
8539 * res_n_m2: nop
8540 * res_n_m1:
8541 *
8542 * PLTresolve:
8543 * addis 11,11,(1f-res_0)@ha
8544 * mflr 0
8545 * bcl 20,31,1f
8546 * 1: addi 11,11,(1b-res_0)@l
8547 * mflr 12
8548 * mtlr 0
8549 * sub 11,11,12 # r11 = index * 4
8550 * addis 12,12,(got+4-1b)@ha
8551 * lwz 0,(got+4-1b)@l(12) # got[1] address of dl_runtime_resolve
8552 * lwz 12,(got+8-1b)@l(12) # got[2] contains the map address
8553 * mtctr 0
8554 * add 0,11,11
8555 * add 11,0,11 # r11 = index * 12 = reloc offset.
8556 * bctr
8557 */
8559 {
8560 ADDIS_11_11,
8561 MFLR_0,
8562 BCL_20_31,
8563 ADDI_11_11,
8564 MFLR_12,
8565 MTLR_0,
8566 SUB_11_11_12,
8567 ADDIS_12_12,
8568 LWZ_0_12,
8569 LWZ_12_12,
8570 MTCTR_0,
8571 ADD_0_11_11,
8572 ADD_11_0_11,
8573 BCTR,
8574 NOP,
8575 NOP
8576 };
8578 /*
8579 * Non-PIC glink code is a little simpler.
8580 *
8581 * # ith PLT code stub.
8582 * lis 11,(plt+(i-1)*4)@ha
8583 * lwz 11,(plt+(i-1)*4)@l(11)
8584 * mtctr 11
8585 * bctr
8586 *
8587 * The branch table is the same, then comes
8588 *
8589 * PLTresolve:
8590 * lis 12,(got+4)@ha
8591 * addis 11,11,(-res_0)@ha
8592 * lwz 0,(got+4)@l(12) # got[1] address of dl_runtime_resolve
8593 * addi 11,11,(-res_0)@l # r11 = index * 4
8594 * mtctr 0
8595 * add 0,11,11
8596 * lwz 12,(got+8)@l(12) # got[2] contains the map address
8597 * add 11,0,11 # r11 = index * 12 = reloc offset.
8598 * bctr
8599 */
8601 {
8602 LIS_12,
8603 ADDIS_11_11,
8604 LWZ_0_12,
8605 ADDI_11_11,
8606 MTCTR_0,
8607 ADD_0_11_11,
8608 LWZ_12_12,
8609 ADD_11_0_11,
8610 BCTR,
8611 NOP,
8612 NOP,
8613 NOP,
8614 NOP,
8615 NOP,
8616 NOP,
8617 NOP
8618 };
8625 /* Build the branch table, one for each plt entry (less one),
8626 and perhaps some padding. */
8632 {
8635 }
8637 {
8640 }
8646 /* Last comes the PLTresolve stub. */
8648 {
8649 bfd_vma bcl;
8652 {
8655 }
8669 {
8674 }
8675 else
8676 {
8681 }
8682 }
8683 else
8684 {
8686 {
8689 }
8699 {
8704 }
8705 else
8706 {
8711 }
8712 }
8713 }
8716 }
8717 \f
8718 #define TARGET_LITTLE_SYM bfd_elf32_powerpcle_vec
8720 #define TARGET_BIG_SYM bfd_elf32_powerpc_vec
8722 #define ELF_ARCH bfd_arch_powerpc
8723 #define ELF_MACHINE_CODE EM_PPC
8724 #ifdef __QNXTARGET__
8725 #define ELF_MAXPAGESIZE 0x1000
8726 #else
8727 #define ELF_MAXPAGESIZE 0x10000
8728 #endif
8729 #define ELF_MINPAGESIZE 0x1000
8730 #define ELF_COMMONPAGESIZE 0x1000
8731 #define elf_info_to_howto ppc_elf_info_to_howto
8733 #ifdef EM_CYGNUS_POWERPC
8734 #define ELF_MACHINE_ALT1 EM_CYGNUS_POWERPC
8735 #endif
8737 #ifdef EM_PPC_OLD
8738 #define ELF_MACHINE_ALT2 EM_PPC_OLD
8739 #endif
8741 #define elf_backend_plt_not_loaded 1
8742 #define elf_backend_can_gc_sections 1
8743 #define elf_backend_can_refcount 1
8744 #define elf_backend_rela_normal 1
8746 #define bfd_elf32_mkobject ppc_elf_mkobject
8747 #define bfd_elf32_bfd_merge_private_bfd_data ppc_elf_merge_private_bfd_data
8748 #define bfd_elf32_bfd_relax_section ppc_elf_relax_section
8749 #define bfd_elf32_bfd_reloc_type_lookup ppc_elf_reloc_type_lookup
8750 #define bfd_elf32_bfd_reloc_name_lookup ppc_elf_reloc_name_lookup
8751 #define bfd_elf32_bfd_set_private_flags ppc_elf_set_private_flags
8752 #define bfd_elf32_bfd_link_hash_table_create ppc_elf_link_hash_table_create
8753 #define bfd_elf32_get_synthetic_symtab ppc_elf_get_synthetic_symtab
8755 #define elf_backend_object_p ppc_elf_object_p
8756 #define elf_backend_gc_mark_hook ppc_elf_gc_mark_hook
8757 #define elf_backend_gc_sweep_hook ppc_elf_gc_sweep_hook
8758 #define elf_backend_section_from_shdr ppc_elf_section_from_shdr
8759 #define elf_backend_relocate_section ppc_elf_relocate_section
8760 #define elf_backend_create_dynamic_sections ppc_elf_create_dynamic_sections
8761 #define elf_backend_check_relocs ppc_elf_check_relocs
8762 #define elf_backend_copy_indirect_symbol ppc_elf_copy_indirect_symbol
8763 #define elf_backend_adjust_dynamic_symbol ppc_elf_adjust_dynamic_symbol
8764 #define elf_backend_add_symbol_hook ppc_elf_add_symbol_hook
8765 #define elf_backend_size_dynamic_sections ppc_elf_size_dynamic_sections
8766 #define elf_backend_hash_symbol ppc_elf_hash_symbol
8767 #define elf_backend_finish_dynamic_symbol ppc_elf_finish_dynamic_symbol
8768 #define elf_backend_finish_dynamic_sections ppc_elf_finish_dynamic_sections
8769 #define elf_backend_fake_sections ppc_elf_fake_sections
8770 #define elf_backend_additional_program_headers ppc_elf_additional_program_headers
8771 #define elf_backend_grok_prstatus ppc_elf_grok_prstatus
8772 #define elf_backend_grok_psinfo ppc_elf_grok_psinfo
8773 #define elf_backend_write_core_note ppc_elf_write_core_note
8774 #define elf_backend_reloc_type_class ppc_elf_reloc_type_class
8775 #define elf_backend_begin_write_processing ppc_elf_begin_write_processing
8776 #define elf_backend_final_write_processing ppc_elf_final_write_processing
8777 #define elf_backend_write_section ppc_elf_write_section
8778 #define elf_backend_get_sec_type_attr ppc_elf_get_sec_type_attr
8779 #define elf_backend_plt_sym_val ppc_elf_plt_sym_val
8780 #define elf_backend_action_discarded ppc_elf_action_discarded
8781 #define elf_backend_init_index_section _bfd_elf_init_1_index_section
8782 #define elf_backend_post_process_headers _bfd_elf_set_osabi
8786 /* VxWorks Target */
8788 #undef TARGET_LITTLE_SYM
8789 #undef TARGET_LITTLE_NAME
8791 #undef TARGET_BIG_SYM
8792 #define TARGET_BIG_SYM bfd_elf32_powerpc_vxworks_vec
8793 #undef TARGET_BIG_NAME
8796 /* VxWorks uses the elf default section flags for .plt. */
8799 {
8807 }
8809 /* Like ppc_elf_link_hash_table_create, but overrides
8810 appropriately for VxWorks. */
8813 {
8818 {
8826 }
8828 }
8830 /* Tweak magic VxWorks symbols as they are loaded. */
8831 static bfd_boolean
8839 {
8841 valp))
8845 }
8847 static void
8849 {
8852 }
8854 /* On VxWorks, we emit relocations against _PROCEDURE_LINKAGE_TABLE_, so
8855 define it. */
8856 #undef elf_backend_want_plt_sym
8857 #define elf_backend_want_plt_sym 1
8858 #undef elf_backend_want_got_plt
8859 #define elf_backend_want_got_plt 1
8860 #undef elf_backend_got_symbol_offset
8861 #define elf_backend_got_symbol_offset 0
8862 #undef elf_backend_plt_not_loaded
8863 #define elf_backend_plt_not_loaded 0
8864 #undef elf_backend_plt_readonly
8865 #define elf_backend_plt_readonly 1
8866 #undef elf_backend_got_header_size
8867 #define elf_backend_got_header_size 12
8869 #undef bfd_elf32_get_synthetic_symtab
8871 #undef bfd_elf32_bfd_link_hash_table_create
8872 #define bfd_elf32_bfd_link_hash_table_create \
8873 ppc_elf_vxworks_link_hash_table_create
8874 #undef elf_backend_add_symbol_hook
8875 #define elf_backend_add_symbol_hook \
8876 ppc_elf_vxworks_add_symbol_hook
8877 #undef elf_backend_link_output_symbol_hook
8878 #define elf_backend_link_output_symbol_hook \
8879 elf_vxworks_link_output_symbol_hook
8880 #undef elf_backend_final_write_processing
8881 #define elf_backend_final_write_processing \
8882 ppc_elf_vxworks_final_write_processing
8883 #undef elf_backend_get_sec_type_attr
8884 #define elf_backend_get_sec_type_attr \
8885 ppc_elf_vxworks_get_sec_type_attr
8886 #undef elf_backend_emit_relocs
8887 #define elf_backend_emit_relocs \
8888 elf_vxworks_emit_relocs
8890 #undef elf32_bed
8891 #define elf32_bed ppc_elf_vxworks_bed
8892 #undef elf_backend_post_process_headers